Today railway vehicles, in particular passenger vehicles, are in practice only constructed as self-supporting metal structures. A vehicle body comprising a substructure, side walls, end walls and a roof is constructed. The substructure must withstand operating forces, in particular loading, clutch pressure and tensile forces. For this reason the substructure is frequently designed as a frame and usually comprises two external longitudinal beams as well as several cross-members connecting these longitudinal beams and is reinforced at the ends of the vehicle.
The economic production of railway vehicles requires a high level of automation during manufacture. In particular, the production of a large number of welded connections should be automated. Consequently, today automated production of the substructures, side walls and the roof already takes place on suitable welding machines. The connection of the substructure to the side walls or the side walls to the roof can currently only be performed partially by means of automatic welding, as all known welding machines must be able to readily access the welded seams. However, the welded seams between the substructure and the side walls or between the side walls and the roof inside the wagon body are only accessible with difficulty and must be produced manually. In order to provide connection points which can be welded using automation, WO 2011/038751 A1 discloses a divided longitudinal beam, wherein one part of said longitudinal beam is welded to one major component (substructure, side wall or roof) in each case, and which has straight, readily accessible connection points which can be welded using automation when the associated major component is added. If this solution is used for the side wall/substructure connection point, then penetration of the cross-members of the substructure into the part of the longitudinal beam which is assigned to the substructure is necessary. These penetrations require that one of the welds which connect the two parts of the longitudinal beam to a closed profile must be interrupted at these connection points. This penetration cannot be omitted in such a longitudinal beam for reasons of strength, however.